A bit cliché, but I tried to come up with a list of items I could stuff in a bottle that I would really like to have with me in a wilderness survival setting.

1. wide mouth Nalgene bottle
2. sawyer portable water filter
3. turbo type bic lighter wrapped in 3 feet of duct tape
4. tongue depressor wrapped with 5 feet of electrical tape, 4 feet of duct tape, and 30 feet of 100+ lb test Dacron fishing line.
5. 4 10p nails
6. Micron flashlight
7. 4 packets instant coffee
8. Leatherman Wave
9. Contractor grade garbage bag
10. Cup that fits on the end of the bottle
11. 4 zip fizz plastic vials, one full of ibuprofen, one full of multivitamins, one full of Benadryl caplets, and one full of paraffin/Vaseline cotton balls
12. 6 ounces of pemmican triple wrapped in heavy duty aluminum foil.
13. Fox Micro whistle

All of this will fit in the Nalgene bottle, except the cup that goes on the outside (maintains volume and form factor). Basically it was everything I could think to stuff in the bottle. This list completely discounts any other edc, so it is likely that many of these things would already be on my person anyways. But my intent is to list items I would really want to have with me (besides clothing) to get by for a reasonable amount of time. One item not on the list of course is a gun, which is a high priority for me. But mine would not fit in the bottle anyways.